Do not keep files opened. When xtrabackup opens tablespace it normally doesn’t close its file handle in order to handle the DDL operations correctly. However, if the number of tablespaces is really huge and can not fit into any limit, there is an option to close file handles once they are no longer accessed. Percona XtraBackup can produce inconsistent backups with this option enabled. Use at your own risk.

This option tells xtrabackup to compress all output data, including the transaction log file and meta data files, using the specified compression algorithm. The only currently supported algorithm is ‘quicklz’. The resulting files have the qpress archive format, i.e. every *.qp file produced by xtrabackup is essentially a one-file qpress archive and can be extracted and uncompressed by the qpress file archiver.

This option specifies the number of worker threads used by xtrabackup for parallel data compression. This option defaults to 1. Parallel compression (‘–compress-threads’) can be used together with parallel file copying (‘–parallel’). For example, ‘–parallel=4 –compress –compress-threads=2’ will create 4 IO threads that will read the data and pipe it to 2 compression threads.

When creating an incremental backup, you can specify the log sequence number (LSN) instead of specifying --incremental-basedir. For databases created by MySQL and Percona Server 5.0-series versions, specify the LSN as two 32-bit integers in high:low format. For databases created in 5.1 and later, specify the LSN as a single 64-bit integer. ##ATTENTION##: If a wrong LSN value is specified (a user error which XtraBackup is unable to detect), the backup will be unusable. Be careful!

There is a large group of InnoDB options that are normally read from the my.cnf configuration file, so that xtrabackup boots up its embedded InnoDB in the same configuration as your current server. You normally do not need to specify these explicitly. These options have the same behavior that they have in InnoDB or XtraDB. They are as follows:

This option specifies the path to the file containing the list of databases and tables that should be backed up. The file can contain the list elements of the form databasename1[.table_name1], one element per line.

Causes xtrabackup to create a file called xtrabackup_suspended in the --target-dir. Instead of exiting after copying data files, xtrabackup continues to copy the log file, and waits until the xtrabackup_suspended file is deleted. This enables xtrabackup and other programs to coordinate their work. See Scripting Backups With xtrabackup.

This option specifies the destination directory for the backup. If the directory does not exist, xtrabackup creates it. If the directory does exist and is empty, xtrabackup will succeed. xtrabackup will not overwrite existing files, however; it will fail with operating system error 17, fileexists.

If this option is a relative path, it is interpreted as being relative to the current working directory from which xtrabackup is executed.

This option affects how much memory is allocated for preparing a backup with --prepare, or analyzing statistics with --stats. Its purpose is similar to innodb_buffer_pool_size. It does not do the same thing as the similarly named option in Oracle’s InnoDB Hot Backup tool. The default value is 100MB, and if you have enough available memory, 1GB to 2GB is a good recommended value. Multiples are supported providing the unit (e.g. 1MB, 1M, 1GB, 1G).